// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "ui/views/controls/single_split_view.h"

#include <stddef.h>

#include "base/logging.h"
#include "base/macros.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "ui/events/event_utils.h"
#include "ui/views/controls/single_split_view_listener.h"

namespace {

static void VerifySplitViewLayout(const views::SingleSplitView& split)
{
    ASSERT_EQ(2, split.child_count());

    const views::View* leading = split.child_at(0);
    const views::View* trailing = split.child_at(1);

    if (split.bounds().IsEmpty()) {
        EXPECT_TRUE(leading->bounds().IsEmpty());
        EXPECT_TRUE(trailing->bounds().IsEmpty());
        return;
    }

    EXPECT_FALSE(leading->bounds().IsEmpty());
    EXPECT_FALSE(trailing->bounds().IsEmpty());
    EXPECT_FALSE(leading->bounds().Intersects(trailing->bounds()));

    if (split.orientation() == views::SingleSplitView::HORIZONTAL_SPLIT) {
        EXPECT_EQ(leading->bounds().height(), split.bounds().height());
        EXPECT_EQ(trailing->bounds().height(), split.bounds().height());
        EXPECT_LT(leading->bounds().width() + trailing->bounds().width(),
            split.bounds().width());
    } else if (split.orientation() == views::SingleSplitView::VERTICAL_SPLIT) {
        EXPECT_EQ(leading->bounds().width(), split.bounds().width());
        EXPECT_EQ(trailing->bounds().width(), split.bounds().width());
        EXPECT_LT(leading->bounds().height() + trailing->bounds().height(),
            split.bounds().height());
    } else {
        NOTREACHED();
    }
}

class SingleSplitViewListenerImpl : public views::SingleSplitViewListener {
public:
    SingleSplitViewListenerImpl()
        : count_(0)
    {
    }

    bool SplitHandleMoved(views::SingleSplitView* sender) override
    {
        ++count_;
        return false;
    }

    int count() const { return count_; }

private:
    int count_;

    DISALLOW_COPY_AND_ASSIGN(SingleSplitViewListenerImpl);
};

class MinimumSizedView : public views::View {
public:
    MinimumSizedView(gfx::Size min_size)
        : min_size_(min_size)
    {
    }

private:
    gfx::Size min_size_;
    gfx::Size GetMinimumSize() const override;
};

gfx::Size MinimumSizedView::GetMinimumSize() const
{
    return min_size_;
}

} // namespace

namespace views {

TEST(SingleSplitViewTest, Resize)
{
    // Test cases to iterate through for horizontal and vertical split views.
    struct TestCase {
        // Split view resize policy for this test case.
        bool resize_leading_on_bounds_change;
        // Split view size to set.
        int primary_axis_size;
        int secondary_axis_size;
        // Expected divider offset.
        int divider_offset;
    } test_cases[] = {
        // The initial split size is 100x100, divider at 33.
        { true, 100, 100, 33 },
        // Grow the split view, leading view should grow.
        { true, 1000, 100, 933 },
        // Shrink the split view, leading view should shrink.
        { true, 200, 100, 133 },
        // Minimize the split view, divider should not move.
        { true, 0, 0, 133 },
        // Restore the split view, divider should not move.
        { false, 500, 100, 133 },
        // Resize the split view by secondary axis, divider should not move.
        { false, 500, 600, 133 }
    };

    SingleSplitView::Orientation orientations[] = {
        SingleSplitView::HORIZONTAL_SPLIT,
        SingleSplitView::VERTICAL_SPLIT
    };

    for (size_t orientation = 0; orientation < arraysize(orientations);
         ++orientation) {
        // Create a split view.
        SingleSplitView split(
            new View(), new View(), orientations[orientation], NULL);

        // Set initial size and divider offset.
        EXPECT_EQ(test_cases[0].primary_axis_size,
            test_cases[0].secondary_axis_size);
        split.SetBounds(0, 0, test_cases[0].primary_axis_size,
            test_cases[0].secondary_axis_size);
        split.set_divider_offset(test_cases[0].divider_offset);
        split.Layout();

        // Run all test cases.
        for (size_t i = 0; i < arraysize(test_cases); ++i) {
            split.set_resize_leading_on_bounds_change(
                test_cases[i].resize_leading_on_bounds_change);
            if (split.orientation() == SingleSplitView::HORIZONTAL_SPLIT) {
                split.SetBounds(0, 0, test_cases[i].primary_axis_size,
                    test_cases[i].secondary_axis_size);
            } else {
                split.SetBounds(0, 0, test_cases[i].secondary_axis_size,
                    test_cases[i].primary_axis_size);
            }

            EXPECT_EQ(test_cases[i].divider_offset, split.divider_offset());
            VerifySplitViewLayout(split);
        }

        // Special cases, one of the child views is hidden.
        split.child_at(0)->SetVisible(false);
        split.Layout();

        EXPECT_EQ(split.size(), split.child_at(1)->size());

        split.child_at(0)->SetVisible(true);
        split.child_at(1)->SetVisible(false);
        split.Layout();

        EXPECT_EQ(split.size(), split.child_at(0)->size());
    }
}

TEST(SingleSplitViewTest, MouseDrag)
{
    const int kMinimumChildSize = 25;
    MinimumSizedView* child0 = new MinimumSizedView(gfx::Size(5, kMinimumChildSize));
    MinimumSizedView* child1 = new MinimumSizedView(gfx::Size(5, kMinimumChildSize));
    SingleSplitViewListenerImpl listener;
    SingleSplitView split(
        child0, child1, SingleSplitView::VERTICAL_SPLIT, &listener);

    const int kTotalSplitSize = 100;
    split.SetBounds(0, 0, 10, kTotalSplitSize);
    const int kInitialDividerOffset = 33;
    const int kMouseOffset = 2; // Mouse offset in the divider.
    const int kMouseMoveDelta = 7;
    split.set_divider_offset(kInitialDividerOffset);
    split.Layout();

    gfx::Point press_point(7, kInitialDividerOffset + kMouseOffset);
    ui::MouseEvent mouse_pressed(ui::ET_MOUSE_PRESSED, press_point, press_point,
        ui::EventTimeForNow(), 0, 0);
    ASSERT_TRUE(split.OnMousePressed(mouse_pressed));
    EXPECT_EQ(kInitialDividerOffset, split.divider_offset());
    EXPECT_EQ(0, listener.count());

    // Drag divider to the bottom.
    gfx::Point drag_1_point(
        5, kInitialDividerOffset + kMouseOffset + kMouseMoveDelta);
    ui::MouseEvent mouse_dragged_1(ui::ET_MOUSE_DRAGGED, drag_1_point,
        drag_1_point, ui::EventTimeForNow(), 0, 0);
    ASSERT_TRUE(split.OnMouseDragged(mouse_dragged_1));
    EXPECT_EQ(kInitialDividerOffset + kMouseMoveDelta, split.divider_offset());
    EXPECT_EQ(1, listener.count());

    // Drag divider to the top, beyond first child minimum size.
    gfx::Point drag_2_point(
        7, kMinimumChildSize - 5);
    ui::MouseEvent mouse_dragged_2(ui::ET_MOUSE_DRAGGED, drag_2_point,
        drag_2_point, ui::EventTimeForNow(), 0, 0);
    ASSERT_TRUE(split.OnMouseDragged(mouse_dragged_2));
    EXPECT_EQ(kMinimumChildSize, split.divider_offset());
    EXPECT_EQ(2, listener.count());

    // Drag divider to the bottom, beyond second child minimum size.
    gfx::Point drag_3_point(
        7, kTotalSplitSize - kMinimumChildSize + 5);
    ui::MouseEvent mouse_dragged_3(ui::ET_MOUSE_DRAGGED, drag_3_point,
        drag_3_point, ui::EventTimeForNow(), 0, 0);
    ASSERT_TRUE(split.OnMouseDragged(mouse_dragged_3));
    EXPECT_EQ(kTotalSplitSize - kMinimumChildSize - split.GetDividerSize(),
        split.divider_offset());
    EXPECT_EQ(3, listener.count());

    // Drag divider between childs' minimum sizes.
    gfx::Point drag_4_point(
        6, kInitialDividerOffset + kMouseOffset + kMouseMoveDelta * 2);
    ui::MouseEvent mouse_dragged_4(ui::ET_MOUSE_DRAGGED, drag_4_point,
        drag_4_point, ui::EventTimeForNow(), 0, 0);
    ASSERT_TRUE(split.OnMouseDragged(mouse_dragged_4));
    EXPECT_EQ(kInitialDividerOffset + kMouseMoveDelta * 2,
        split.divider_offset());
    EXPECT_EQ(4, listener.count());

    gfx::Point release_point(
        7, kInitialDividerOffset + kMouseOffset + kMouseMoveDelta * 2);
    ui::MouseEvent mouse_released(ui::ET_MOUSE_RELEASED, release_point,
        release_point, ui::EventTimeForNow(), 0, 0);
    split.OnMouseReleased(mouse_released);
    EXPECT_EQ(kInitialDividerOffset + kMouseMoveDelta * 2,
        split.divider_offset());

    // Expect intial offset after a system/user gesture cancels the drag.
    // This shouldn't occur after mouse release, but it's sufficient for testing.
    split.OnMouseCaptureLost();
    EXPECT_EQ(kInitialDividerOffset, split.divider_offset());
    EXPECT_EQ(5, listener.count());
}

} // namespace views
